Valence Bond Theory: Overlap of Atomic Orbitals

1
Valence Bond Theory Overlap of Atomic Orbitals
s bond - overlap of s orbitals
H-H

s bond - overlap of s orbital and p orbital
H-F
1 s bond - head/head overlap of p orbitals 2 p
bonds - sidewise overlap of p orbitals
Bonds with hybridization of atomic orbitals
sp3 hybridization
C atom 4 s bonds - overlap of H-s orbitals and
sp3 orbitals Of C
H
CH4
C
2s
2p
A single sp3 orbital, each with single electron
sp3
sp2 hybridization
(O also hybridized See next page)
H
H2CO
C
O
H
A single sp2 orbital, each with single electron
sp hybridization
CO2
C atom 2 s bonds 2 p bond
O
C
O
A single sp orbital, each with single electron
2
Dinitrogren 2 Models
without hybridization with just p electrons
1 s bond - head/head overlap of p orbitals 2 p
bonds - sidewise overlap of p orbitals
2nd sp orbital
with sp hybridization with all valence electrons
N
N2
1st sp orbital one with nonbonded pair
1 s bonds 2 p bond
2s
2p
N
N
p
sp
O atom in H2CO (previous page)

• geometry around O is trigonal planar
• requires 3 equivalent orbitals from the O
• hence, sp2 hybridization

O
2s
2p
p
sp2